[cdog]

I've done this trip many times, and it takes 8-10 days to get out there, and 2.5 days to get back (on the interstate). You can go about 250 miles per day in the more populated states, maybe 400 a day in the desert states. This is providing you stop for lunch and see the usual attractions. Some things (Meramac Caverns, Fantastic Caverns, etc.) take a while to get through. I would recommend a good guidebook, as the route isn't marked very well outside of Illinois.

You need to stop in a hotel NO later than 6 PM if you want anything resembling decent parking. Otherwise, you'll have to leave your Cobra way out in some side lot (no thanks!). If you are taking a Passat, this won't be an issue, and you can drive until dusk every day.

The vintage hotels sound quaint, but aside from the better ones (Wagon Wheel, Munger Moss, Blue Swallow) they tend to be filled with the kind of people that stay in $30 hotels (think meth making operations). For security reasons, I usually stay in Hampton Inns.

Bring tools, fix a flat, and a firearm... I've needed the tools and firearm a few times.